DOI: 10.1002/open.201600023
Synthesis of b-Hydroxysulfides from Thiophenols and
Disulfides with tert-Butyl Hydroperoxide as the Oxidant
and Reactant
Jian-Bo Feng[a, b] and Xiao-Feng Wu*[a, b]
In this Communication, we developed a new procedure for the
synthesis of b-hydroxysulfides from thiophenols or diaryl disul-
fides with TBHP as the oxidant. In the presence of zinc iodide
or potassium iodide, with TBHP as the oxidant and pre-reac-
tant, thiophenols and diaryl disulfides reacted with the methyl
group of tBuOH smoothly and selectivity to give the corre-
sponding 2-methyl-1-(arylthio)propan-2-ols as the terminal
products in moderate to good yields.
of thiophenols with epoxides, but the selectivity is problematic
(Scheme 1a).[9] Alternatively, procedures based on the reaction
between alkenes and thiophenols (Scheme 1b)[10] or phenyl-
thiomethyltrimethylsilane
and
carbonyl
compounds
(Scheme 1c) have also been developed.[11] However, drawbacks
tert-Butyl hydroperoxide (TBHP) is one of the most commonly
used organic oxidants in organic chemistry. tert-Butanol, the
expected product after oxidation reactions, is usually consid-
ered as waste. From the view point of sustainable develop-
ment, it will be interesting if there is a procedure can use tert-
butanol as the reactant when using TBHP as the oxidant.
On the other hand, sulfur-containing compounds hold nu-
merous important applications in various areas and many
pharmaceutical, agrochemical, and naturally occurring prod-
ucts contain at least one sulfur atom in their core structures.[1]
Among the plentiful sulfurated chemicals, b-hydroxysulfides
represent a class of compounds with high interest and impor-
tance. They have been found to exist in pharmaceuticals and
natural products.[2] In synthetic chemistry, b-hydroxysulfides
are excellent substrates for the synthesis of allylic alcohols,[3]
benzoxathiepines,[4] benzotiazepines,[5] a-thioketones,[6] a-sub-
stituted a,b-unsaturated enones,[7] and b-hydroxysulfoxides.[8]
These procedures have also been applied in the synthesis of
natural products. Based on the importance of b-hydroxysul-
fides, many synthetic methodologies have been developed for
their preparation. The most explored procedure is the reaction
Scheme 1. Procedures for the preparation of b-hydroxysulfides.
include the availability and stability of substrates as well as low
yield; in addition, the selectivity issue still needs to be solved.
Using this background information, we developed a new pro-
cedure for b-hydroxysulfide preparation. With thiophenols and
disulfides as the substrates, using TBHP as the oxidant and it’s
by-product as the reaction partner, the desired b-hydroxysul-
fides were synthesized in moderate to good yields
(Scheme 1d). The Csp3ÀH bond in the methyl group of tert-bu-
tanol, which is the by-product of the TBHP oxidant, was
smoothly and selectivity cleaved.
[a] J.-B. Feng, Prof. Dr. X.-F. Wu
Department of Chemistry
In the optimized reaction system, toluene was found to be
the most suitable solvent for this reaction. This surprised us, as
the reaction of thiophenols with toluene, using TBHP as the
oxidant, has previously been explored.[12] However, neither the
reaction of thiophenol with the solvent nor the further oxida-
tion of the product was observed in our system. ZnI2 was
found to be the best catalyst here; lower yields were obtained
when CuI, I2, or TBAI were tested. No product could be detect-
ed with MeCN, cyclohexane, or iPrOH as the reaction media.
During the substrate testing, as shown in Table 1, moderate to
good isolated yields were generally obtained. Good yields can
be achieved with electron-donating substituted thiophenols.
Interestingly, the methylthio substituent can be tolerated and
gives the corresponding 2-methyl-1-[(4-(methylthio)phenylth-
Zhejiang Sci-Tech University
Xiasha Campus
Hangzhou, Zhejiang Province 310018 (P. R. China)
[b] J.-B. Feng, Prof. Dr. X.-F. Wu
Leibniz-Institut fꢀr Katalyse e.V. an der Universitꢁt Rostock
Albert-Einstein-Strasse 29a
18059 Rostock (Germany)
Supporting Information for this article can be found under http://
ꢀ 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
distribution in any medium, provided the original work is properly cited,
the use is non-commercial and no modifications or adaptations are
made.
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